Are Table Saw Support Legs Necessary?

I need some advice. On a Grizzly G0833P t/s [cabinet hybrid] can I add a “Big Dog” cast iron router table extension if I bolt it to the existing table wing and the fence rails without adding support legs? It weight 55lbs, my router weighs 17lbs and the fence is another 8 plus whatever I’m routing….all totaled less than 90bs. Could it bend or break something? The t/s is on a mobile base…will it make it tippy?

I have mounted a cast iron extension by extending my fence rails on both sides of the extension and drilling and bolting it on both ends of the extension. My fence rails are heavy 2” square steel and are sufficient to hold the weight of the extension and router, I have not had any tipping problems.